Unilever, in partnership with PSI and Facebook, hopes to harness the social graph to address one of the world’s most critical challenges: access to clean water… When [Facebook] users sign up to Waterworks, they partner with an individual waterworker, making the connection personal. The waterworker in the field is equipped with a smartphone, able to send updates back to partners through photos and videos. The updates post to the partner’s Facebook page, so all of their connections also see the impact the donation is making- how many liters of water the donation has provided and the number of people whose lives have been changed by the clean water.